Make errorsDisabled an option

[ahmedalsudani]

That would make more sense conceptually, and it would allow us to declare it at the time we create an instance as in var hs = hackStack(..., {'errorsDisabled': true})

The obvious drawback to this is the high likelihood that someone will spell it wrong and wonder why our API is acting weird... I just realized that

[ahmedalsudani]

At the time this issue was opened, I did not realize disabling errors was a global setting. In light of that knowledge, this issue is obsolete